Refrigerator cabinet



Feb. 29, 1944. J. H. ASH BAUGH REFRIGERATOR CABINET Filed Sept. 4, 1941 FIG- ' INVENTOR I FIG- 3. FIG. 4-

Jomv H. JSHEAUGH 'ATTO EY Patented Feb. 29, 1944 2 343 1 "REFRIGERATOR CABINET John H. Ashbau'gh, Longmeadow, Mass., assignor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa., a corporation of Pennsylvania Application September 4, 1941, Serial No. 409,485

11 Claims.

This invention relates to refrigerator cabinets and more especially to the arrangement of imperforate shelves therein.

Imperforate shelves in domestic refrigerators are desirable because of the decreased dehydration of foods stored in uncovered dishes in refrigerators equipped with such shelves. Imperforate shelves of transparent glass are additionally desirable because of the unobstructed view afforded to the contents of the refrigerator and because of the ease with which glass shelves are cleaned. Imperforate' shelves, however, have not been generally used in domestic refrigerators because they unduly obstruct the convectional circulation of air therein so that the portions of the refrigerator at a distance from the cooling unit, are not properly cooled. Where such shelves have been used, either special means have been-employed for refrigerating the areas at a distance from the cooling unit or very large air-circulating openings around or through the shelves have been provided which unduly reduce the storage space on the shelf.

It is an object of the invention to provide arefrigerator having imperforate shelves and having relatively small air-circulating openings.

Another object of the invention is to provide imperforate shelves in domestic refrigerator cabinets, which shelves provide a maximum of shelf space and a minimum of obstruction to the air circulation through the cabinets.

A further object of the invention is to provide transparent shelves in domestic refrigerator cabinets which do not unduly obstruct the air circulation in the cabinets.

These and other objects are effected by my invention as will be apparent from the following description and claims taken in connection with the accompanying drawing, forming ,a part of this application, in which:

Fig. 1 is an elevation of a domestic refrigerpartment ll comprises an inner liner 13 of metal and an outer shell l4 spaced from the top and the side walls of the food liner l3 and continued downwardly thereof to enclose the machine compartment I 2. The inner liner l3 and shell I 3 form fiat vertical side walls 6, a rear wall I and a horizontal top wall 8. A partition I5 spaced from the lower wall of the food-storage compartment forms a division wall. between the machine compartment 12 and the food-storage chamber ll. Loose heat-insulating material I1 is packed around the inner liner l3 to fill the space betweenthe inner liner l3 and the outer shell I4 and partition IS. The entire front of the food-storage chamber II is open to provide access thereto, and the edge adjacent the opening of the inner liner I3 is turned outwardly and the edge of the outer shell I4 is turned inwardly to form attachment flanges forvbreaker strips i8 which surround the access opening.

The opening of the food-storage chamber is closed by a door l9 which forms the front wall thereof when the door I8 is closed. The door it comprises an outer dished shell 2| of metal and an inner panel 22 of rigid heat-insulating material. The edges of the outer shell 2i are turned inwardly and secured to the edges of the inner panel 22 to form a hollow door structure, the

interior of which is filled with loose heat-insuator with the door thereof opened to an angle of cation of the invention.

Referring to the drawing for a detailed description of the invention, the reference'numeral Iii designates a domestic refrigerator comprising a rectangularly-shaped food-storage chamber II in the upper portion thereof and a machine compartment I2in the lower portion. The food comlating material 23. A sealing gasket 24 is secured at the outer edge of the door and makes contact with the breaker strips l8 when the door I! is closed. The door l9, side walls 6, back wall I and horizontal walls l5 and 8 form the generally rectangular food-storage compartment having four vertically-extending corners It.

An evaporative cooling unit 26 is secured cen trally'in the upper portion of the food-storage chamber II. The coolingunit 26 comprises two refrigerant-carrying side walls 21, a refrigerant carrying bottom wall 28, and a refrigerant-carrying shelf 29 in theuppr portion of the cooling unit 26. A door 3| closes the front wall of the cooling unit 28 and a plate forms the upper wall 32 thereof. The door 3! is preferably notairtight. The area between the upper wall 32 and the refrigerated shelf 29 at the rear of the cooling unit 26 is closed by a plate 33. The rear portion of the evaporator below the refrigerai'it-carrying shelf 29 is'open and a shelf 34 is located in the lower portion of the cooling unit 26. The rear portion of the cooling element 26 is, therefore, in better heat-conducting relationship with the all in the food-storage compartment than the A number of generally-rectangular glass shelves 3! are supported below the cooling unit 26 in the food-storage compartment II and another glass shelf 38 forms the cover of a vegetable-storage chamber 39. The side edges 4| of the shelves 31 are located closely adjacent the side walls of the inner liner but the rear edges 42 and the front edges 43 of the shelves 3'! are spaced from the rear wall of the food liner l3 and from the inner panel 22 of the door I9, respectviely, to provide narrow air passages.

In an insulated cabinet of the character described, the greatest heat leakage occurs at the cabinet door and principally at the joint between the cabinet and the door. This heat leakage raises the temperature of the air adjacent the door i9, and the air will rise upwardly through the spaces between the edges 43 of the shelves and the door IS. The relatively warm air will row rearwardly across the cooling unit 26 and will be cooled, A portion of the air will enter at the upper portion of the opening in the rear of the cooling unit 26, will be cooled to low temperature therein, and thereupon flow out at the lower portion of the opening in the rear of the cooling unit 25 and down the spaces between the ear edges 42 of the shelves 2'! and the rear wan the inner liner l3. The air will thereafter flow below shelves 31 toward the door i9 and will again be warmed and repeat its circulating cycle. The arrows in Fig. 2 depict the air circulation described.

It will be observed that the air passages are located in the ath of the natural convectional air currents the refrigerator, and for this reason adequate cooling of the lower portion of the food-storage chamber is secured even though the passages are relatively narrow. In practice, it has been found advisable to make the air passages at the rear edges 42 of the shelves 3'! somewhat larger than those at the front edges 3 because the air passages at the rear are more likely to become partially obstructed by materials on the shelf being pushed back against the rear wall of the food-storage chamber.

In a comparative test of a refrigerator containing glass shelves shaped according to the modification shown in Fig. 3 and a similar refrigerator equipped with open wire shelves, it was found that with two glass shelves each having an area of 407 square inches and air passages of 13 square inches at the front edge of each shelf and 27 square inches at the rear edge thereof, the temperature below the lowest shelf was approximately 2 F. higher and the temperature above and near the top shelf was approximately 2 F. lower in the refrigerator equipped with glass shelves than in the one equipped with w re shelves. The incidental air spaces at the side edges of the glass shelves were 5% square inches at each edge. During the test, the shelves were loaded with comestibles representing average conditions of service.

A more effective location of the air-circulating, passages in the food-storage compartment is shown in the modification illustrated by Fig. 4. In this modification, the central portion of the front edges 41 of the shelves 46 are located near the inner panel 22 of the door l9 and the front corners of the glass shelves adjacent the air gap between the door I9 and the front edge of the side walls of thefood-storage chamber Hv are cut away to provide air passages. It is mainly at the front corners of the food-storage chamber ii that heat leakage into the chamber H occurs because of heat leakage through the gasket 24 and through the air gap between the door and the front edge of the side walls of the chamber I l, and because of heat leakage along the heat breaker strips l8 and the adjacent portion of the inner panel 22. The air in this area is also subjected to heat leakage through both the door is and the side wall 8 of the food-storage chamber H.

The corner portions of the rear edges 48 of the shelves 48 extend into the rear corners Ii of the food-storage chamber II, and the central portions of the rear edges 48 of the glass shelves 46 are cut away to provide air passages at the rear of the inner liner IS. The cut-out area at the rear edges 48 of the glass shelves 48 is directly below the opening in the rear of the cooling unit 26 to provide a. downward passa e of the cold air issuing therefrom. The rear corners of the glass shelves 48 are carried into the rear corners l6 of the food-storage chamber H because the air in these corners is subjected to' heat leakage both through the rear wall I of the insulated storage chamber as well as through the side wall 6 of the same. It, therefore, is warmer than the adjacent air and would not circulate downwardly vigorously, and for that reason to corner area is more properly reserved for the storage of foods. In the modification of Fig. 4, the air ducts at the glass shelves are thus more nearly located at those areas of the foodstorage chamber H where the natural convectional air currents are most vigorous.

It will be apparent from the above that this invention provides imperforate shelves in a. domestic refrigerator cabinet, which shelves may be transparent and which provide a maximum of shelf surface while providing a minimum obstruction to the natural convectional air currents in the refrigerator and therefore to the cooling action of the cooling unit. While I have shown my invention in several forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof, and I desire,'therefore, that only such limitations shall be placed thereupon as are specifically set forth in the appended claims.

What I claim is:

1. In a refrigerator cabinet, the combination of insulated top, bottom, and side walls defining a food-storage chamber, one of said side walls having an access opening, an insulated door for said opening, said one side wall, when the door is closed, being of less heat-insulating value per unit of area than any other side wall of said food-storage chamber, a cooling unit in heat exchange relationship with the air inthe upper portion of the chamber and a rectangular shelf of continuous solid material below said upper portion of the chamber and spaced from the" bottom wall thereof to provide a combined air passage and storage space for foods, said shelf being constructed to provide also an air passage adjacent said door and a further air passage adiacent the central portion of the side wall opposite said door, the shelf having a close fit with the other opposed side walls and preventpast the shelf adjacent the major portions of the tangularly-shaped food-storage chamber embodying front, side, rear, top, and bottom heatinsulating walls, said front wall embodying a door opening and a door for said opening, said front wall, when the door is closed, being of lower heat-insulating value per unit of area than any other wall of said chamber, a cooling unit in the upper portionof said chamber, and

a substantially rectangular shelf of continuous solid material in said chamber below said cooling unit and spaced from the bottom wall of said chamber to provide a'combined air passage and storage space for foods, the front and the rear edges of said shelf being spaced from the front and the rear walls, respectively, of said chamber to provide ducts for the circulation of air, said circulation being downwardly from said cooling unit along the rear wall of said chamber, below said shelf, and upwardly along the front wall of said chamber to said. cooling unit, the shelf having a close fit with the side walls and preventing circulation. of air past the shelf adjacent the major portions of the .width of said side walls.

3. In a refrigerator, the combination of a rectangularly-shaped food-storage chamber embodying front, side, rear, top, and bottom heatinsulating walls, said front wall embodying a door opening and a door for said opening, said front wall when the door is closed. being of lower heat-insulating value per unit of area than any other wall portion of said chamber, a cooling unit in the upper portion of said chamberand extending into close proximity to the rear wall thereof, and a substantially rectangular shelf of continuous solid material in said chamber below said cooling unit and spaced from the bot,-

tom wall of said chamber to provide a combined -air passage and storage space for foods, the

front and the rear edges of said shelf being spaced from the front and the rear walls, respectively, of said chamber to provide ducts for the circulation of. air, said circulation being downwardly from said cooling unit' along the rear wall of said chamber, below said shelf, and

upwardly along the front wall of said chamber to said cooling unit, the shelf having a close fit with the side walls and preventing circulation of air past the shelf adjacent the major portions of the width of said side walls.

, solid material in said chamber below said cool- 4. In a refrigerator, the combination of a rectangularly shaped food-storage chamber embodying front, side, rear, top, and bottom heatinsulating walls, said front wall embodying a door opening and a door for said opening, sald front wall, when the door is closed, being of lower heat-insulating value per unit of area than any other wall portion of said chamber, a cooling unit in the upper portion of said chamber and a substantially rectangular shelf of continuous solid material in said chamber below said cooling unit and spaced from the bottom wall of said chamber, the front and the rear edges of said shelf being spaced from the front and the rear walls, respectively, of said chamber to provide ducts for. the circulation of air, said circulation being downwardly from said cooling unit along the rear wall of said chamber, below said shelf, and upwardly along the front wall of said chamber to said cooling unit, the space between the rear wall and the rear edge of the shelf being larger, than the space between the front edge of the shelf and the front wall of said chamber, the shelf having a close fit with the side walls and preventing circulation of air ing unit and spaced from the bottom wall of said chamber, the front and the rear edges of said shelfbeing spaced from the front and the rear walls, respectively, of said chamber to provide ducts for the circulation of air, and the side edges of said shelf being closely adjacent the side walls of said chamber for substantially the entire length of said'side edges of said shelf. f

6. In a refrigerator, the combination of front, side and back vertical walls and top and bottom horizontal walls defining a rectangular food storage chamber and forming'four 'verticallyextending corners thereof, said front wall comprising a door for closing the food storage chamber and having portions of higher heat conductivity than the back wall and, therefore, having portions of higher temperature than the back wall, a cooling elementdisposed in the upper portion of the food-storage chamber to cool and induce circulation of air therein, and a generally rectangular imperforate shelf disposed intermediate said horizontal walls and extending substantially flush with'the side walls of tne food-storage'chamber and also substantially to the rear vertical corners thereof, said imperforate shelf, with the front andback walls, forming vertical air passages adjacent the front and rear walls, respectively, whereby the air circulation induced by the cooling element passes downwardly through the air passage adjacent the back wall and upwardly through the air passage adjacent the front wall because of the higher temperature of the front wall.

7. In a refrigerator, the combination of front, side and back vertical walls and top and bottom horizontal walls defining a rectangular food storage chamber and forming four verticallyextending corners thereof, said front wall comprising a door for closing the food-storage chamber and having portions of higher heat conductivity than the back wall and, therefore, having portions of higher temperature than the back wall, a cooling element disposed in the upper portion of the food storage chamber to cool and induce circulation of air therein, and a generally rectangular imperforate shelf disposed intermediate said horizontal walls and extending substantially'flush with the side walls of the food-storage chamber and also substantially to the rear vertical corners thereof, said imperforate shelf, with the front and back walls, forming vertical air passages adjacent the front and rear walls, respectively, whereby the air circulation induced by the cooling element passes downwardly through the air passage adjacent the back wall and upwardly through the air passage adjacent the front wall because of the higher temperature of the front wall, said cooling element having front and back portions adjacent the front and back walls of thechamtionship with the air adjacent the back wall than the front of the cooling element with, the air adjacent the front wall, so that air circulation downwardly through said air passage adjacent the back wall is assisted.

8. In a refrigerator, the combination of front, side and back vertical walls and top and bottom horizontal walls defining a rectangular foodstorage chamber and forming four verticallyextending corners thereof, said front wall comprising a door for closing the food-storage compartment and having portions of higher heat conductivity and, therefore, at a higher temperature than the back wall, a cooling element disposed in the upper portion of the foodstorage chamber to cool and induce circulation of air therein and a plurality of spaced, generally rectangular imperforate shelves disposed intermediate said horizontal walls and extending substantially fiush with the side walls of the food-storage chamber and also substantially to the rear vertical corners there of, each of said imperforate shelves, with the front and back walls, forming vertical air passages adjacent the front and rear walls, respectively, whereby the air circulation induced by the cooling element passes downwardly through the air passages adjacent the back wall and upwardly through the air passages adjacent the front wall because of the higher temperature of the front wall.

9. In a refrigerator cabinet, the combination of insulated front, side, rear, top, and bottom walls forming a rectangular food-storage chamher, said front wall having a door opening therein, adoor for said opening, at least one edge of said. opening and one edge of said door forming a vertical joint of relatively low heat-insulating value, a cooling unit in the upper portion of said chamber near the rear wall but spaced from the side walls thereof, and a substantially imperforate shelf in said chamber, said shelf having side edges extending contiguously along the side walls of said chamber, said shelf being spaced from said vertical joint to define an air--, circulating opening adjacent thereto and spaced also from the central portion of the rear wall to define a second air-circulating opening, whereby the convectional air currents in the food storage chamber circulate downwardly in said second-named air-circulating opening and upwardly in said first-named air-circulating opening.

10, In a refrigerator cabinet, the combination of insulated front, side, rear, top, bot- 5 tom walls forming a rectangular food-storage chamber, said front wall having a door opening therein, a door for said opening, at least one edge of said opening and one edge of said door forming a vertical joint of relatively low heatinsulating value, a cooling unit in the upper portion of saidchamber and spaced from the side walls thereof, said cooling unit making I" re intimate contact with the air in the rear tion of the storage chamber than with the air in 15 the front portion thereof, and a substantially imperforate shelf in said chamber, said, shelf being spaced from said vertical joint ;cdefine an air-circulating opening adjacent thereto spaced also from the central portion of the rear as wall to define a second air-circulating opening, whereby the convectionai air currents in the food-storage chamber circulate downwardly in said second-named air-circulating opening a c. ipwardly in said first-named air-circulating 26 opening.

11. In a refrigerator, the combination of an insulated, rectangularly-shaped food-storage chamber embodying front, rear, and side vertical walls, and horizontal top and bottom walls,

86 one of said vertical walls being of lower heatinsulating value than any other vertical wall of equal area of said chamber, a cooling unit in the upper portion of said chamber, and a substantially rectangular shelf of continuous solid mate- 35 rial in said chamber below said cooling unit and spaced from the bottom wall of said chamber to provide a combined air passage and storage space for foods, said shelf being also spaced from said vertical wall of lower heat-insulating value and 0 from another of said vertical walls opposite said walls of lower heat-insulating value, the spaces between said shelf and said first opposed vertical walls and the space below said shelf providing ducts for the circulation of air around said shelf, said circulation being upwardly along the wall of lower heat-insulating value of said chamber, the shelf having a close fit with the other opposed vertical calls and preventing circulation of air past the shelf adjacentthe major to portion of the width of saidrwalls.

. JOHN H. ASHBAUGH.

' CERTIFICATE OF. CORRECTION. I c Patent No. 2,5L 3 ,i66-. K 7 1, February-29, 19th,

toss a. ASHBAUGH.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, second column, line 30, for the word "to" before"corner" re ad--th'--; page 14., second column, line 141, claim ll, for "walls" read --wall-; line 148,- same claim, for "calls" read--wall sline 50, same claim 11, after "said walls." and before the signature insert the following claims ,12. Inarefri-gerator cabinet, the combination of first, second, third, and fourth vertical walls and two horizontal walls joined together to form a rectangularly shaped food-storage chamber having said first and second wall opposite to one another, said first vertical wall being of higher heat-insulating value than said second vertical wall, a cooling unit in heat exchange relationship with the air in the upper portion of said chamberr'and a substantially rectangular,imperforate, and horizontal shelf in said chamber below said cooling unit and extending substantially to the third and fourth vertical walls and substantially from corner to corner of the food-storage chamber except for small spaces adjacent said first and second vertical walls,

saidshelf being spaced from'the first and second ver 'ticsl walls of the cabinet to define an air passage adjacent each of said first and second walls, whereby the air in said cabinet is chilled by the cooling unit circulates downwardly --through the air passage adjacent said second wall, passes below the shelf, and circulates upwardly through the air passage 'adiacent said first wall and passes above'the shelf to said c'ooling unit.

5. In a refrigerator comprising an insulated chamber having front, side, and rear vertical walls, a top and a bottom wall, said front wall being of lowerheet insulat-. ingvalue per .unit of area than said side rear walls, and a cooling unit in the upper portion of said chamber, the combination'of an imperforate and approximately re ctangular shelf in said chamber below said cooling unit and spaced from said bottom wall to provide a combined air passage and storage'spacein said chamber, said dielf having front, side, and rear edges, at least aportion of said front edge being spaced from the front wall and at least a portion of said rear edge being spaced 'from the rear wall of said chamber to provide an air passage ad- Jacent said front and adjacent said rear wall, the side edges of said shelf lying adjacent the respective side walls of said chamber.

in the heading to the printed specification, line 8 thereof, for'll Claims read 13 claims"; and that the said Letters Patent should be read with this correction therein that the same may confom to the record of the case in the Patent Office.

Signed and sealed this 25m a of April, A. D. 191 1;.

Leslie Frazer (seal) Acting Commissioner of Patents. 

